In vitro activity of Ticarcillin/clavulanic acid against Aerobic Gram-negative Bacilli

Background : Resistance of gram-negative bacilli is mostly due to production of β-lactamases. Resistance of Enterobacteriaceae to ticarcillin/clavulanic acid (TICCV), reported to be rare in the United States, is not known in Korea. The aim of this study was to determine the activity of TICCV against aerobic gram-negative bacilli. Methods : Activity of TICCV was compared with those of carbenicillin, piperacillin and ticarcillin by the NCCLS agar dilution method against aerobic gram-negative bacilli isolated from patients at a tertiary care hospital. Results : MIC90 of TICCV were low against E. coli, K. oxytoca, P. vulgaris, Providencia sp., Y. enterocolitica, A. baumannii and X. maltophilia. Resistance rates to TICCV were low, except for E. cloacae, E. aerogenes, S. marcescens and P. aeruginosa. Conclusions : The in vitro test result indicated that TICCV should be more effective than the other antimicrobial agents for the treatment of infections due to aerobic gram-negative bacilli.ope